From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D96C72147E6 for ; Mon, 3 Aug 2026 17:14:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785777292; cv=none; b=Pzp4hXwYNscVqR33W3GrFuAx4sSZeG/CRaZPlIOnQELs+V4xunjM2As4zpgguvKMXz+XVEiKMFUODi7ajGJoHiidFW+7EdphIag2sfyI+1r7nridFESbGWPhSCgDGykd4R+La619cdwJql1/TfBK2lIcK42ZlvYWBoANaMJWo40= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785777292; c=relaxed/simple; bh=a48o3jwP9ErVvNTdsqlBCScRW0OkUrRHaz6QshGmefc=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=t0nohQn+EYBv5m4AvCVnRhPxZj3Adl3CjdyZIXlhdbalVCBUb5VGsYLSuCVyBADaZ5z39p+1EXAa1Kd5qP++EtXcHz64iF+Sjs/m/IgKGR1A1eZLCXIZk2YlQ93/CxqBodFsEYRqKgtjYjpyNu+XpCmmiHUjsa4YWnhqe1WObAs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ZzSPsA2l; arc=none smtp.client-ip=209.85.210.197 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--almasrymina.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ZzSPsA2l" Received: by mail-pf1-f197.google.com with SMTP id d2e1a72fcca58-84842381150so7187565b3a.3 for ; Mon, 03 Aug 2026 10:14:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1785777290; x=1786382090; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=yOW3n52VHLe0DVF46hmkA+PwFM2h9qnGl//NaQ6CV/A=; b=ZzSPsA2l1K8g2ell5mUcUfVAYgD+OGESmiLwFP04AYRpHlJQE7TL8o/BIZvQ8MJuXy prgVEgUwl426rdEJ5C5sIUHY0HtWgNON5JU12pfkQ6sunpytwdrzhNG9gG+UE2TNezka 5cnComwJ5e5qDcIMjSnUqSJILUIUF8BGBkdQY9ASZ9/F+iUBc7Bo+AEF9ncusTWK989o 17DghbDjC07VfLgjTGnx6SYApMYzHxSIOmRc7w+n09hYyQ/8SpVYnJF3FWEahO+JKWpJ 2/uYcKv0GAwLkhSTKTnO1hLur+JDOK32WO6qbQSuaaO7/b7Y53wCXkfc70oYMBEuruAm zZ5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785777290; x=1786382090; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=yOW3n52VHLe0DVF46hmkA+PwFM2h9qnGl//NaQ6CV/A=; b=Xq2apl4IGrxjr69qmxQ/MH3QcKrfRCk/fiB7g22oMC/RZ6jr4xlHX2KD8RGZLWyyNY i+UHPwNfal3gwQKPwlQ5OtjRPJGiPQgNA75GdNVZvOisWItzDlSX8vAT7JpNjbsMoF9r irOsfFDbjiUKVZTMB2+9O9Kd1AvjZhYjWMek2RKFyzR6mSd07UT9sOB8oL1aEye0Gjlo VNHv33NENcbCJwdcRXGySRWNpl0SuZfILcePh7HCI97OHBYhaCuKwFbXm8fCAS11a+Rb kFKBuYVMrK0kri8nPOEREKMy5QXiJDepRVzJyjMsGKCzEAbvrQW48WBq4ZX49wlLmTck nC1A== X-Forwarded-Encrypted: i=1; AHgh+RoHyIrBhL9s0IZo8XBoC6s5NVrBP/BVllDDBTShoMiW89W7lMcRIgaVCC6u6eN38SlcjfOEihcGcyC6bEI=@vger.kernel.org X-Gm-Message-State: AOJu0Yw4/tD7J9SM2IzVfTV6Bvq6CXTWeG+vzD5ogJijdhzeiAgwALNH p3cUnP1k5P8DcZVI6YRyeXurfP4aIaMsZvVqK7Zh2+720Au+W+AhFBtDfBNp5J6Fy7q3rgFMFE6 Qq7kY4ToTJTgVHY3AWx+utm/sfw== X-Received: from dycue2.prod.google.com ([2002:a05:7300:82:b0:30c:1aab:2586]) (user=almasrymina job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:6a05:b0:3b4:7eb0:47a1 with SMTP id adf61e73a8af0-3c92a53b04cmr11334168637.19.1785777289991; Mon, 03 Aug 2026 10:14:49 -0700 (PDT) Date: Mon, 3 Aug 2026 17:14:40 +0000 In-Reply-To: <20260803171441.408014-1-almasrymina@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260803171441.408014-1-almasrymina@google.com> X-Mailer: git-send-email 2.55.0.571.g244d577d93-goog Message-ID: <20260803171441.408014-2-almasrymina@google.com> Subject: [PATCH net v2 2/3] net: devmem: return EMSGSIZE on type mismatch From: Mina Almasry To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, kerneljasonxing@gmail.com, kuniyu@google.com, bjorn@kernel.org, jiayuan.chen@linux.dev, kaiyuanz@google.com, willemb@google.com, asml.silence@gmail.com, sdf@fomichev.me, bobbyeshleman@gmail.com, fw@strlen.de, Mina Almasry , Neal Cardwell , Ralf Lici , Will Deacon Content-Type: text/plain; charset="UTF-8" When a devmem payload mixes with a standard page payload, return -EMSGSIZE instead of -EFAULT. This enables tcp_sendmsg to seamlessly fall back to creating a new segment instead of failing the socket send. Fixes: bd61848900bff ("net: devmem: Implement TX path") Cc: Pavel Begunkov Cc: Stanislav Fomichev Cc: Bobby Eshleman Signed-off-by: Mina Almasry Reviewed-by: Pavel Begunkov --- net/core/datagram.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/datagram.c b/net/core/datagram.c index 173b5d97bd409..6f8ffd61bcab4 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -638,7 +638,7 @@ int zerocopy_fill_skb_from_iter(struct sk_buff *skb, int frag = skb_shinfo(skb)->nr_frags; if (!skb_frags_readable(skb)) - return -EFAULT; + return -EMSGSIZE; while (length && iov_iter_count(from)) { struct page *head, *last_head = NULL; @@ -713,7 +713,7 @@ zerocopy_fill_skb_from_devmem(struct sk_buff *skb, struct iov_iter *from, struct net_iov *niov; if (i && skb_frags_readable(skb)) - return -EFAULT; + return -EMSGSIZE; /* Devmem filling works by taking an IOVEC from the user where the * iov_addrs are interpreted as an offset in bytes into the dma-buf to -- 2.55.0.571.g244d577d93-goog